Pandemic refers to an epidemic that spread over several countries, normally affecting a large number of people [1]. Coronavirus has recently been detected in the Wuhan region of China in December 2019. The World Health Organization (WHO) used the term 2019 novel coronavirus to refer to the new coronavirus that affected the lower respiratory tract. This virus causes various symptoms, such as pneumonia, fever, breathing difficulty and lung infection, etc. This respiratory infection can be transmitted through droplets of various sizes. According to current evidence, the COVID-19 virus is primarily transmitted between people through respiratory droplets and contact routes. These viruse gradually spread across the globe. Considering the rate of spread, it became alarming and called for urgent attention by world leaders to combat the menace. In the war against COVID-19, health system resilience, accountability and integrity are more important than ever. The health systems of some high-incomecountries have become overwhelmed as a result of the rising number of morbidity and mortality due to COVID-19. The less resilient health systems of many low and middle-income countries (Nigeria is included), are even more vulnerable. With the high population as well as high population density in most part of the country, the risk of transmission and spread of the virus can never be overemphasized. If urgent and deliberate steps in the right direction are not taken by various stakeholders, the health system is at edge of complete collapse [2].
Introduction: Bioresonance is a holistic physical method that can be used diagnostically and therapeutically to treat various diseases. Bioresonance uses the electromagnetic waves it receives from the patient. This biophysical method of treatment alters the energy field of the affected organism, increasing the effectiveness of the autoimmune system, thus improving the patient’s overall health. Methods: A quasi-experimental design was used to examine whether bioresonance had an effect on the symptoms of the patients. Statistical data processing involves a study of various parameters such as age, gender, studies, occupation, intolerance or illness as well as the existence and balancing of allergic charges. The study included 311 patients from doctors and bio-coordinating laboratories in Athens, Thessaloniki, Volos and Xanthi. The sample of the study included both men (120 subjects - 38.58%) and women (191 subjects – 61.42%), aged from 2 to 76 years old. The age group with the largest number of patients included those aged from 31 to 45. Results: The patients under treatment came forward with symptoms mostly nasal (61.09%), followed by eye, respiratory, cutaneous, and gastrointestinal symptoms. Most of the patients (90%) observe no symptoms at all or show significant improvement of their symptoms after a period of 12 months of bioresonance treatment. These results show that bioresonance intervention had a significant effect on the improvement of symptoms and this improvement is even obvious 12 months after the intervention; p<.01. Conclusion: We believe that the forthcoming results contribute to a better understanding of the effect of bioresonance on the human body and its affect in preventing and restoring health issues.
Childhood cancer incidence in Suriname (South-America) was estimated using secondary data from 1980 to 2008, and these findings were stratified according to gender; age groups < 1, 1-4, 5-14, and 15-19 years; and the largest ethnic groups (Hindustanis, Maroons, Creoles, and Javanese).Data were expressed as total numbers, proportions, average yearly numbers, and/or crude incidence rates per 1,000,000 population per year.There were 290 malignancies in the period covered, i.e., about 10 new cases per year or 24 per 1,000,000 per year.The average yearly number of overall cancer increased from approximately 1 every two years in newborns to 3-4 per year in adolescents and young adults.Thirty to 35% of patients were Hindustani or Creole; the proportions of Javanese and Maroons patients were about twice and five times, respectively, lower.Leukemias and lymphomas comprised almost half of cases, each occurring 2 to 3 times per year.Bone tumors, soft-tissue sarcomas, and carcinomas were the most common non-hematological malignancies, occurring once or twice per year.Central nervous system tumors, neuroblastoma, retinoblastoma, renal tumors, primary hepatic tumors, and germ cell tumors were exceedingly rare.In conclusion, childhood cancer incidence in Suriname was relatively low; the individual histiotypes displayed an unusual ranking; and there were differences in the sex, age, and ethnic distribution of overall cancer as well as certain histiotypes.However, these observations might be biased by the use of crude rates, and underdiagnosis and incomplete registration of cases due to the absence of specialized (pediatric) cancer facilities in the country.
Effects of exposures to the PM 2.5 in ambient air have increasingly attracted attention of health communities and government regulatory agencies as it has been implicated with a growing list of adverse health effects, including cardiopulmonary issues, premature death and lung cancer.However, the rates of adverse health effects and long term exposure to PM 2.5 in different populations have not been well quantified due to the lack of data.In this article, 25,427 daily PM 2.5 concentrations collected from the 73 air monitoring stations throughout Taiwan are extrapolated to 290 townships by Kriging method using GIS data.These townships are then stratified into 5 levels (in µg/m 3 ) of PM 2.5 : 20-24, 25-29, 30-34, 35-39, 40 and above.Data on female lung cancer mortality taken from national statistics and the estimated PM 2.5 concentrations, considered as an exposure biomarker are combined to assess the effect of PM 2.5 on lung cancer.The average annual PM 2.5 concentration in Taiwan is 35.6±0.4 µg/m 3 .It is estimated that lung cancer mortality has a mean increase of 16% (6%-25%) for each 10 µg/m 3 increment of PM 2.5 concentration and one out of 9 female lung cancer deaths (11%) in Taiwan is attributed to the PM 2.5 exposures.This assessment is conducted using the commonly accepted principle of making the best use of available data for the stated objective.The limitations of data and the resultant conclusion are carefully articulated and discussed to advance further research.
Objectives: To explore two different approaches to calculate average exposure in occupational cohorts using a large occupational cohort as an example.The data for occupational cohort exposed to acrylonitrile was collected and analyzed previously by NCI; outcome was lung cancer.Methods: Both approaches use cumulative exposure as the numerator.As the denominator, one uses the duration of exposure, while the other uses the length of employment.The former approach is used when detailed exposure history is available, and the latter is used when exposure history is less detailed.The differences are investigated for a large occupational cohort.Results: With restricting the cohort to only those with enough latency for lung cancer, the cumulative exposure divided by the length of employment is a significant predictor of the lung cancer mortality, while cumulative exposure divided by the duration of exposure (average intensity) is not.Analysis is shown not to be positively confounded by smoking. Conclusion:Both approaches should be considered when calculating an average exposure metric.
Background: Statistical frequentist techniques are sometimes misinterpreted or misused, while Bayesian techniques seem to present several practical advantages, such as accommodating small sample sizes, unobserved variables along with measurement errors and incorporating information from previous studies.The primary objective of this study was to evaluate the association between waterpipe dependence and chronic obstructive pulmonary disease (COPD), by comparing frequentist and Bayesian methods' results.Methods: It is a multicenter case-control study, comparing a group of COPD patients with a control group.COPD diagnosis was held after clinical and paraclinical testing, while a standardized questionnaire was used to evaluate smoking history.Both frequentist and Bayesian analyses were performed.Results: Although carried out on the same dataset, the results quantitatively differed between the frequentist and Bayesian analysis.Whenever the frequentist results were clear cut such as in case of cigarette smoking association with COPD, performing the MCMC method helped to increase the accuracy of the results, but did not change the direction of hypothesis acceptance, except in doubtful cases.When the frequentist p-value was ≤0.100, such as in case of smoking more than 15 waterpipe-years, the MCMC method improved deciding between the null and alternative hypothesis. Conclusion:The Bayesian approach may have advantages over the frequentist one, particularly in case of a low power of the frequentist analysis, due to low sample size or sparse data; the use of informative priors might be particularly useful in narrowing credible interval and precising the choice between the null and alternative hypothesis.In case of borderline frequentist results, the MCMC method may be more conservative, particularly without priors.However, in case of large sample sizes, using frequentist methods is preferred.
Exposing unmasked US Army recruits to elevated levels of o-chlorobenzylidene malononitrile (CS tear gas) during Mask Confidence Training (MCT) increases the risk of Acute Respiratory Illness (ARI) diagnosis in the period following CS exposure when compared to the period before exposure.All Army Activities Message (ALARACT) 051/2013 was implemented in March 2013 to reduce CS exposure concentrations during MCT and associated ARI rates.This observational, prospective cohort studied CS exposures and associated ARI health outcomes after implementation of ALARACT 051/2013 in 5 298 recruits attending US Army Basic Combat Training (BCT).These data indicate a 10-fold reduction (p<0.001) in CS exposure concentrations; recruit exposures ranged from 0.26 -2.78 mg/m 3 (=1.04mg/m 3 ) and chamber operator exposures from 0.05 -2.22 mg/m 3 (=1.05mg/m 3 ).The overall risk of ARI diagnosis following CS exposure also decreased when compared to period before exposure (RR=1.79,95%CI=1.29,2.47) resulting in 26.85% (95%CI=-0.17,0.54) intervention effectiveness.Post-chamber ARI rates were dependent upon CS exposure concentration (p=0.02), and pre/post-chamber ARI rate ratios were significantly elevated at all concentration categories higher than the Threshold Limit Value Ceiling (TLV-C) (0.39 mg/m 3 ).Results support previous research suggesting risk of ARI diagnosis after CS exposure is positively associated with CS concentration.
Epidemiological study results have a key role in the assessment of health risks associated with exposures to chemicals and pollutants, and often serve as the basis for the development of regulatory limits for environmental and occupational health. A key uncertainty in the application of epidemiological study results in risk assessments stems from variability in defining and operationalizing the concept of consistency of findings across studies, with assessments of consistency often a controversial component of risk assessments. Although assessment of consistency of findings across a diverse collection of epidemiological studies is central to evaluating that body of evidence for supporting causal inferences, the variability in definition and formal evaluation methods strongly suggest the need for constructive approaches to consistently and transparently evaluate data consistency. In response to the need to improve approaches to assessing consistency in epidemiological study results, the Johns Hopkins Risk Sciences and Public Policy Institute organized a workshop held in Baltimore, Maryland in September 2010 to identify and discuss key methodological issues, and to develop recommendations for qualitative and quantitative approaches to addressing those issues. A multi-disciplinary approach was utilized for the workshop, involving invited experts from a variety of fields, and the invited participants were drawn from academia, industry, government, and the public interest sectors. This report provides a summary of selected epidemiology methodological issues discussed by the workshop participants and provides the workshop’s key findings and recommendations for future approaches to addressing this issue.
Regression models have been used to control confounding in food borne cohort studies, logistic regression has been commonly used due to easy converge. However, logistic regression provide estimates for OR only when RR estimate is lower than 10%, an unlikely situation in food borne outbreaks. Recent developments have resolved the binary model convergence problems applying log link. Food items significant in the univariable analysis were included for the multivariable analysis of two recent Finnish norovirus outbreaks. We used both log and logistic regression models in R and Bayesian model in Winbugs by SPSS and R. The log-link model could be used to identify the vehicle in the two norovirus outbreak datasets. Convergence problems were solved using Bayesian modelling. Binary model applying log link provided accurate and useful estimates of RR estimating the true risk, a suitable method of choice for multivariable analysis of outbreak cohort studies.
The genus Cryptococcus includes at least 37 different species, of which, two are important human pathogens: Cryptococcus neoformans and Cryptococcus gattii. These fungi are opportunistic pathogens and etiologic agents of cryptococcosis disease in humans and animals. A variety of virulence factors interfere with the establishment of cryptococcal infection is usually acquired via inhalation of environmental basidiospores or desiccated yeasts. Cryptococcosis has gained medical importance over the last decade due to the AIDS pandemic, and become an emerging pathogen of immunocompetent individuals, especially in children. This disease in humans may involve every tissue, including cutaneous and pulmonary sites, but the most serious manifestation is central nervous system involvement with meningoencephalitis. In this review, we briefly described the taxonomy, the fungus biology, epidemiology and clinical manifestations of cryptococcosis in immunocompetent and immunocompromised individuals.
Introduction: Waterpipe smoking gained popularity during recent years. Although waterpipe smoking exposes people to the same noxious substances found in cigarettes, popular belief considers it harmless. Our objective was to evaluate the association between waterpipe smoking and dependence, and COPD. Methods: We conducted a case-control study in two tertiary care hospitals. Cases were included if diagnosed as COPD by a pulmonologist and confirmed by post-bronchodilator FEV1/FVC<0.7; controls were included if free of any respiratory disease or symptom. After oral consent, a standardized questionnaire was administered and spirometry results were collected. Results: 211 COPD cases and 527 controls were studied. In previous smokers, any smoking type was associated with COPD. The ORs were 29.0[14.3-58.8] (p<0.001) for previous cigarette smoking, 11.7[4.4-31.2] (p<0.001) for previous waterpipe smoking, and 44.1[16.3-4.4] (p<0.001) for previous mixed smoking. In current smokers, the ORs were 20.5[10.2-41.2] (p<0.001) for cigarette smoking, 1.8[0.5-5.9] (p=0.299) for waterpipe smoking, and 9.4[3.81-23.0] (p<0.001) for mixed smoking. Nevertheless, we found in waterpipe current smokers, an OR=8.9[3.9-20.7] (p<0.001) for the association between dependence evaluated by LWDS-11 scale, and COPD. These results were confirmed by stratified and multivariate analysis, after adjustment for cigarette smoking and confounding variables. A cumulative smoking of one waterpipe per week for 20years (or its equivalent) was predictive of higher risk of COPD. Discussion: Whereas evidence showing harmful effects of waterpipe smoking is sparse, this study showed a high OR between the risk of developing COPD and being an ex-smoker of waterpipe, or a current waterpipe dependent individual. Additional studies are necessary to confirm our results.
Background: Despite the supply of artemisinin-based combination therapy (ACT) drugs to public health facilities in Nigeria, the uptake of these drugs appear to have remained suboptimal with low improvement in childhood morbidity and mortality. Aim: To use a controlled study to estimate the factors affecting the uptake of ACT in public health facilities in Cross River State (CRS), Nigeria. Methods: The design of this study was cross sectional analytical. The study was carried out in two sites, Akpabuyo (experimental) and Obudu (control) Local Government Areas (LGA) in the south and northern parts of CRS, Nigeria, respectively. Multidisciplinary research team consists of health professionals, biomedical and social scientists who worked with staff of the target facilities. Validated semi-structured questionnaires were administered by trained interviewers on respondents of consecutive households selected by multi-stage sampling procedure. Results: A total of 1250 households (588 in Akpabuyo and 662 in Obudu LGAs) were assessed. More informants in Obudu had formal education than in Akpabuyo (p<0.0001). Mortality of U5 children was higher in Akpabuyo. Stepwise regression analysis showed that farmers (p = 0.009) and people without formal education (p = <0.0001) were less likely than older age group (p = <0.0001) to access anti-malaria drugs in Akpabuyo. Religious beliefs (p=0.003) also predicted uptake of ACTs in Obudu. Conclusion: Informants' occupation, age, education and religious beliefs were key determinants of uptake of ACTs in public health facilities in Nigeria. We recommend targeted malaria education programmes to explore the belief systems in treating fevers in children in this population.
In 2007, diseases caused by Vibrio vulnificus and other Vibrio species became nationally notifiable in the United States because of the potential severity of bloodstream infections. Direct contact of open wound with seawater and the ingestion of contaminated oysters are the principal modes of transmission. Presently, no clear environmental predictors of oyster contamination are known. This study is the first to report an apparent association between rainfall and Vibrio counts at five South Florida beaches. Using multiple regression and ANOVA, the relationship between Vibrio populations and various environmental factors were examined. Vibrio counts ranged from 135 CFU/100 mL at Hollywood Beach to 186,000 CFU/100 mL at North Miami Beach. Vibrio vulnificus and parahemolyticus were detected (less than 1% of all identified isolates) at two and four beaches respectively. Temperature and rainfall dates were the most significant correlates of the incidence of pathogenic Vibrio species.
Ascertainment of lifetime occupational exposures in an epidemiological study of chronic obstructive pulmonary disease (COPD) is important in order to investigate its effect on the disease and develop prevention strategies. The aim of our paper is to describe and evaluate a methodology used to assign lifetime occupational exposure to participants in a case-control study of COPD where lifetime occupational history was ascertained through telephone questionnaire interviews. The methodology involved assigning to each individual a qualitative index of potential exposure to eight occupational hazards, summarized individually overall the job categories reported by the individual, and an overall qualitative index of lifetime exposure to all eight hazards. The eight occupational hazards scored were mineral dusts, metal dusts/fumes, organic dusts, irritant gases/vapors, sensitizers, organic solvents, diesel exhaust, and environmental tobacco smoke (ETS). Two industrial hygienists independently assigned the above indices based on: their expert opinion, a priori knowledge based on literature review, and study participants’ responses to interviewer questions regarding types and duration of exposure. To evaluate agreement of the assigned scores, we used the Kappa statistic to test the agreement between the two scorers on each of the indices. The Kappa statistic generally indicated good agreement between the industrial hygienists’ scores but varied by exposure from 0.42 to 0.86. Although the exposure scoring is somewhat subjective, it is based on experience of experts and review of the literature. This method, with subject interviews providing qualitative lifetime exposure data when air monitoring has not been conducted, is useful for reconstructing lifetime exposures.
Practical and ethical constraints mean that many clinical and/or epidemiological questions cannot be answered through the implementation of a randomized controlled trial. Under these circumstances, observational studies are often required to assess relationships between certain exposures and disease outcomes. Unfortunately, observational studies are notoriously vulnerable to the effect of different types of “confounding,” a concept that is often a source of confusion among trainees, clinicians and users of health information. This article discusses the concept of confounding by way of examples and offers a simple guide for assessing the impact of is effects for learners of evidence-based medicine.
Five studies that evaluated five different quality-improvement initiatives for the prevention of central line-associated bloodstream infections (CLABSIs) in adult, pediatric and/or neonatal intensive care units (ICUs) and that were published within the past two years in an infection-control and epidemiology journal were reviewed, assessed and compared. Each is a prospective cohort study that similarly concludes that the evaluated initiative was responsible for a significant and calculated reduction in the CLABSI rate, ranging from 30.3% to 85%. The soundness of these conclusions and calculations, however, like the legitimacy of several other common uses of CLABSI data, requires, in addition to satisfying a number of other criteria, that each study's CLABSI rates be accurate and complete. The primary goal of this analysis, therefore, was to confirm the hypothesis that each of these five studies had validated its CLABSI rates. The analysis found, however, that these five studies did not validate the accuracy and completeness of their CLABSI rates, which raises reasonable questions about each study’s assessment of and conclusions about the initiative's effectiveness for the prevention of CLABSIs. In addition to their aims, calculations, and conclusions, these five studies share in common a number of features, as well as circumscribing qualities, which are discussed. The distinction between a qualitative assessment and a quantitative determination of an initiative's performance is also discussed. Both the circumspective use of CLABSI data that have not been validated and the cautious interpretation of conclusions about central-line care that are based on these CLABSI data are recommended.
PURPOSE: Research on obesity and the built environment has often featured logistic regression and the corresponding parameter, the odds ratio. Use of odds ratios for common outcomes such obesity may unnecessarily hinder the validity, interpretation, and communication of research findings. METHODS: We identified three key issues raised by the use of odds ratios, illustrating them with data on walkability and body mass index from a study of 13,102 New York City residents. RESULTS: First, dichotomization of continuous measures such as body mass index discards theoretically relevant information, reduces statistical power, and amplifies measurement error. Second, odds ratios are systematically higher (further from the null) than prevalence ratios; this inflation is trivial for rare outcomes, but substantial for common outcomes like obesity. Third, odds ratios can lead to incorrect conclusions during tests of interactions. The odds ratio in a particular subgroup might higher simply because the outcome is more common (and the odds ratio inflated) compared with other subgroups. CONCLUSION: Our recommendations are to take full advantage of continuous outcome data when feasible and to use prevalence ratios in place of odds ratios for common dichotomous outcomes. When odds ratios must be used, authors should document outcome prevalence across exposure groups.
Perceived needs for extensive chemical-specific toxicological information have impeded efforts to assess risks and evaluate likely public health protection benefits of possible standards for hazardous air pollutants (HAPs). This paper discusses opportunities to use effects of HAPs on early effect biomarkers, such as birth weights, to predict likely changes in rare quantal effects of concern that would be relevant for the quantification of likely regulatory benefits from exposure reductions. In the birth weight example, even modest exposures to common air pollutants can be seen as producing a kind of tax on the limited resources available to the fetus to grow and develop. In contrast to teratogenic effects, dose response relationships for fetal growth restriction in animals are often nearly linear, suggesting that the developing fetus may not generally have untapped ”functional reserve capacity“ that is expected to buffer the effects of modest exposures to toxicants in the traditional toxicological paradigm. Given this mechanistic perspective, supported in part by parallel dose response relationships between reported cigarette smoking and both birth weight and infant mortality, restriction on fetal growth can be associated with changes in quantal end effects of concern that are more difficult to assess directly in epidemiological studies.
Using a dataset obtained in an earlier published epidemiological study that revealed the dependence of the probability of subclinical kidney damage in 260 children on the concentration of lead and cadmium in their urine, we have tested some methodological approaches to assessing the type of combined nephrotoxicity produced by these two metals. We have found that the environmentally caused damage to kidneys in children from lead and cadmium is less than additive (manifestation of toxicological antagonism). Given the subadditivity (antagonism) of the damaging effect of lead and cadmium on kidneys as demonstrated on the basis of epidemiological data, we believe that the summation of corresponding risks is a sufficiently conservative principle creating an additional margin of safety and limiting the uncertainty of risk assessment on the whole. Of theoretical interest is the demonstrated consistency of this assessment of the type of combined toxicity irrespective of whether it is carried out on the basis of the paradigm of effect additivity or dose additivity. This enables us to speak in favor of considering the so-called Bliss independence and Loewe additivity as complementary simplified models of the same fairly complex process rather than essentially different biological phenomena. The example studied suggests that approaches to the analysis of epidemiological data for the purpose of assessing combined risk should be tested using each of these models rather than restricting it to one of them based on an a priori choice.
The accuracy of cancer mortality data varies across different cancers.Mortality records and death certificates may not always reflect the true cause of death for various reasons (e.g., misdiagnosis, improper recording on the death certificate, miscoding of the cause of death recorded on the death certificate).Mesothelioma, a rare tumor which is caused by exposure to asbestos, is a special case.Until 1999 when the 10 th revision of the International Classification of Diseases (ICD-10) introduced a specific mesothelioma code, mesothelioma deaths were coded to other causes (e.g., cancer of the pleura, cancer of other or ill-specified sites).Even after the introduction of this mesothelioma code, researchers have shown that estimates of mesothelioma mortality based on death certificates are still biased downward.This article reviews available literature with quantitative information on mesothelioma underascertainment, in particular on different rates of underestimation for pleural and peritoneal mesotheliomas, and suggests two approaches to estimating downward bias in absolute risk estimates due to mesothelioma underascertainment.The choice of approach used depends on whether the information on the proportion of peritoneal mesotheliomas is available.Both approaches are demonstrated and evaluated using a cohort of asbestos workers from Libby, MT.The methods developed in this article may be used in analyses of other asbestos cohorts and in methodologies to predict future mesothelioma burden in populations.Similar approaches can be used to assess the impact of underascertainment of other cancers on risk estimates of other chemicals.
